Sony MZ-B3 Operating Instructions Manual page 39

How the MiniDisc got so small
The 2.5-inch MiniDisc, encased in a
plastic cartridge that looks like a 3.5-
inch diskette, uses a new digital audio
compression technology called
ATRAC (Adaptive TRansform
Acoustic Coding). To store more
sound in less space, ATRAC extracts
and encodes only those frequency
components actually audible to the
human ear.
Quick Random Access
Like CDs, MDs offer instantaneous
random access to the beginning of any
music track. Premastered MDs are
recorded with location addresses
corresponding to each music selection.
Recordable MDs are manufactured
with a "User TOC Area" to contain the
order of the music. The TOC system is
similar to the "directory management
system" of floppy disks. In other
words, starting and ending addresses
for all music tracks recorded on the
disc are stored in this area. This lets
you randomly access the beginning of
any track as soon as you enter the track
number (AMS), as well as label the
location with a track name as you
would file on a diskette.
User TOC
Music Data
Area (recorded data)
Contains the order and
start/end points of the
tracks.
Shock-Resistant Memory
One major drawback of optical read
systems is that they can skip or mute
when subjected to vibration. The MD
system resolves this problem by using
a buffer memory that stores audio
data.
This feature allows you to enjoy
playback while carrying the recorder,
record while holding the recorder, and
so on.
SONY MZ-B3 (E) 3-798-610-22(1)
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